Interexciton nonradiative relaxation pathways in the peridinin-chlorophyll protein

Excitation energy transfer can be unusually efficient and structurally robust when mediated by molecular excitons, which arise in a photosynthetic light-harvesting protein delocalized excitations of the electronic chromophores are created upon absorption light. Here we report results from two-dimensional spectroscopy structure calculations, revealing that excitation is transferred between peridinin chlorophyll excitons peridinin-chlorophyll marine dinoflagellates over delocalized, two-step pathway. Upon light peridinins strong, mid-visible band, trapped chlorophylls less than 50 fs at room temperature. The overall process slowed only few replacement with b. key step pathway transfers higher-energy more extensive delocalization to lowest-energy exciton, 614 neighboring chlorophyll.